The Red Adventure
by FireWithFrost
Summary: What happens when Finn is on another of his adventures? But this time, it's without Jake. He's transported to a different world. There he meets the counterparts from the Land Of Ooo. And then there's Marshall Lee. WARNING: YAOI NOTE- Counterpart of a person: Definition - One that has the same functions and characteristics as another; a corresponding person or thing.
1. Chapter 1

Today was the most depressing day for Finn. Why? He got into an argument with Jake.

"I hope he's not mad..." Finn muttered to himself as he stomped through the Cotton Candy Forest. Lady Rainicorn was thinking of moving in with Jake. Of course, Jake thought she meant with Finn too. But that wasn't the case. She wanted to move into a separate house by themselves.

Jake tried to reason with Finn. That he'd come visit everyday, that they'd still go on adventures..but Finn felt so alone just thinking of the idea..

So. He did what he felt was best. Cut off his friendship with Jake.

"..WHATEVER! WHO NEEDS HIM ANYWAY? I CAN MAKE A NEW FRIEND. OR I CAN BE THE BEST HERO EVER MYSELF!" Finn called out loudly, looking up at the sky.

After a while of thinking, he sighed, now looking down at the floor.  
"As if.." He said quietly, kicking a small stone in his way. "His parents took me in..we've been friends before I could speak...he's done so much..." He muttered.  
"Not to mention the amount of times he's saved my life..." He added on.

Just then, he heard someone singing. It was Marceline sitting on a tree which was near. He thought it'd be best to ignore her and walk on. So he did.

"Yo, Finn!" Marceline called out to him, quickly putting her axe bass around her shoulder and floating down to him.  
"What up, homie?" She asked, grinning, her canines completely visible.

"Nothing much..." Finn sighed yet again.

"No wait-wait-wait. Lemme guess...you got into an argument with Jake and aren't friends anymore?" She asked,a smirk on her face.

Finn nodded. Marceline grinned.

"...Well, I know just what'll cheer you up. C'mon." Marceline grabbed his hand and dragged him over to the entrance of the Evil Forest.

"Sorry Marce, I'm just not in the mood for adventure right now.." Finn muttered.

"Shut it you idiot and listen." Marceline rolled her eyes. She then looked from side to side before leaning in closer to Finn's face, causing the colour in his cheeks to rise.  
"I hear there's a portal around here that takes you to a different world." she whispered, excitement in her voice.

"Whoa-...really?" Finn asked, brightening up slightly. "Wh-where'd you hear that?" He asked, slightly worried about her answer.

"Oh, just a reliable source." Marceline shrugged, leaning back. "Now, you going to help me look for it or what?" she asked back.

"...I guess?.." Finn replied.

Thankfully, they didn't run into any Sign Zombies, Brain Beasts or Skeleton Butterflies. But they didn't find a portal.

"Let's just head back Marce...there's nothing he-" Finn looked around. Marceline wasn't there. It was just a human all by himself in a forest. Normally he wouldn't be this anxious..  
but he just felt uneasy about something.  
"...Marce?" He asked, his tone of worry back in his voice. "Marce, if this is a joke..it's NOT FUNNY." He added on, raising his voice slightly.

No sign of her. No sign of her pure red boots, no sign of her long flowing hair & no sign of anyone.

'..Maybe she's in front of the entrance of the forest..she did say that's where we'd meet if we got split up..' Finn thought.

Just then, Finn turned his head to see a portal. It was blue and managed to illuminate the forest. Truly mystical.

"W-Woah...Marce wasn't lying...it's real...the portal to a different world.." Finn whispered, his whole body now turned around, creeping closer to it until his was in front of it completely.

That's when he felt a person's hand grab his shirt.

"What?" Finn asked.

"Oh, Cake! I got something!" A voice said, overjoyed. The person's hand then pulled Finn into the portal.


	2. Chapter 2

Next thing Finn knew, he was on the floor, patches of dirt on his legs and shorts.

He looked around, sitting up.  
"Wh-"  
He looked behind him to see the portal had disappeared.

"..I-it's a human..." The voice said. Finn looked up to see a girl who looked the same age as him, with the same backpack &  
hat (although the ears were slightly longer..something like a bunny's.). He was taken back at how similar she looked to himself. There was a cat by the girl's side too.

"Y-you're-" Finn was interrupted by the girl giving him a tight hug.

"IT'S A HUMAN! CAKE LOOK! IT'S A HUMAN! A REAL HUMAN!" The girl called out.

Finn's eyes widened.

"SWEET BABIES, IT IS!" Cake beamed."Now you're not the only one Fionna!" She added on.

"YUP!" Fionna let go of Finn grinning broadly.  
"I'm Fionna The Human & this is Cake the Cat!" She introduced.

"F-Finn...MY NAME'S FINN!" He replied, grinning back.

Fionna shaked Finn's hand vigorously.

"We're taking you straight to our home, come on!" Cake said as she grew 10x her normal size. "Hop on!" She smiled.

Fionna jumped onto Cake's back.

"Hey, Jake can do tha-.." Finn stopped what he was saying and frowned. There was no point in bringing Jake up anymore.  
Fionna held her hand out to Finn.  
"C'mon then!"

Finn shook his head, getting Jake out of his thoughts and quickly nodded, taking hold of Fionna's hand which pulled him up.

When they had reached Cake and Fionna's home, Finn's eyes widened.

"H-Hey..this is my house..." Finn said.

"Huh, you sure?" Fionna asked frowning, slightly confused.

After they went inside, Finn looked around and sat on the couch.

'_This is whack dude..'_ Finn thought to himself.

Fionna and Cake sat on the table, looking at Finn, wide smiles on their faces.

"W-What?" Finn asked them both.

"How did you get here?" Fionna asked all of a sudden with curiosity.

"Well, Marceline said there would be a portal to another world, so me and her came here to look for it. But that's when she suddenly left without a word. So I thought it was all a prank of hers..  
but then I saw the portal you pulled me into.." Finn explained. He then raised his eyebrow.  
"What about you guys?" He asked back.

"Well, Marshall Lee said there would be a portal to another world here, so me, Cake and Marshall came here to look for it. But that's when he suddenly left without a word. So me and Cake thought it was all a prank of his..  
but then we saw the portal we pulled you out from!" Fionna replied smiling. She then blinked.  
"Wait..you're from another world?" She asked.

"Yeah, I'm from the Land of Ooo.." Finn replied.

"_But...this is the Land of Ooo, Finn.._" The two girls said in unison, clearly confused.


	3. Chapter 3

Finn stared blankly at the two girls.

"Are you guys crazy?" He asked them, now frowning suspiciously, his arms folded.  
"I'm happy that I've found another human..but that's the only reason I followed you two here! Now you guys are saying this is Ooo!?"

'_What do they mean this IS the land of Ooo!? Am I meant to believe that!? How do I get home?! Something's gone totally wrong! I mean, they're in MY house too!_' Finn had all these thought lodged in his head and couldn't make anything out. He was stressed..with everything...with Jake being gone..and now he's somewhere different and most likely has no way to get back.

Fionna and Cake both looked at each other, slightly worried.  
"When Marshall said the portal leads to a different world...he most likely meant a different dimension.." Fionna guessed.

"Then what? I'm just supposed to believe that this Ooo isn't the Ooo back home?!" Finn snapped at her. "It's not that easy seeing your own home and land in a different dimension with the exact same look to it you know! Anyone would think this isn't a different dimension! Everything is like it is back home! It's hard to believe, wouldn't you think?!"

"Hey calm it! She's just helping!" Cake snapped at Finn. Finn looked surprised and then sighed after a while.

"Sorry..." He muttered, rubbing his eyes, now feeling guilty..he was shouting at the only one of his kind left..and that sort of pained him.

Fionna slapped him around the head.  
"Chill it bro." She said with a smile. "It'll be okay." Finn looked at her and then smiled weakly after a minute. "D'you think you guys can help me get home?" He asked.  
"Oh, of course! We're the heroes of Ooo! We always help those in need" Fionna beamed, flexing (although there was no muscle there.).

"Well for now...we should go to Prince Gumball. He's got all the brains when it comes to cooking so he could help us out." Cake suggested.

"I don't really see how cooking has anything to do with getting me back home..." He replied with a laugh.

"His cooking won't help with you getting back home, but he makes the **best** cookies ever!" Cake complimented.

"Good idea, Cake!" Fionna beamed. Cake and Fionna stood up, as did Finn.

'_These guys are weird...but I think I'll trust them for now.._'

When they reached the 'Candy kingdom', Finn looked around and behind him. It truly was like back home.

'_Seriously..this is a different dimension?_' Finn asked himself, hands in his short's pockets, walking along. Fionna and Cake were in front, talking and laughing together.

"Hey, is there someone I shouldn't get involved with here?" Finn called out to them, not really curious about the answer. He only wanted to make conversation.  
Fionna and Cake turned around and stopped. Finn also stopped walking to see them both thinking.  
"Well...I wouldn't say 'not get involved' with him...but make sure to keep your distance..he's really unpredictable.." Fionna muttered.  
"Who?" Finn asked.

"Marshall Lee." Cake replied.

"Wasn't he the one that left you in the forest?" Finn asked.  
"Yeah.." Fionna replied with a mutter, clenching her fists. "And when I find him, I'm going to murder 'im!"  
"Now, now Fionna...He's very.."  
"He's a jerk." Fionna added on as she helped Cake finish her sentence. "Although he's a good friend of ours, he doesn't know when to stop joking and he just turns everything into a joke. He'll go to any lengths to get what he wants."

"_Aww, d'you really have to make me sound like such a villain?_" Finn quickly looked up to see where the voice came from. He looked over at one of the cotton candy trees to see a boy sitting on one of the branches with a smirk on his face, two of his canines managing to poke out from the corners of his mouth, his hair groomed, but messy at the same time.

The boy had a striking resemblance to Marceline.


	4. Chapter 4

"Anyway, what's up with the dirty little human boy behind you guys? I thought you were the only human left, Fionna?" The boy called out, asking Fionna and Cake, pointing at Finn.

'_Dirty? What does he mean by that?.._' Finn looked down at his clothes to see them printed with dirt, as was his legs and most likely face. '_Oh...when I fell.._'  
Finn frowned, his cheeks red with embarrassment.  
"..Oh wait, I get it. The portal _did _lead to a different dimension after all...That's just a boy from the other dimension..right, right..." The boy brought up all of a sudden, muttering to himself.

"**MARSHALL LEE ABADEER. YOU ARE SO DEAD!**" Fionna called out to him, clenching both of her fists.

"How rude, you could at least answer my question first before threatening me..and wow Fionna, you even know my last name! You must've been investigating a lot about me during your spare time. Heh." The boy replied in a mocking tone, smirking as he looked down at Fionna, who's face was completely red.

He then, after listening to Fionna curse at him at the top of her lungs for ditching herself and Cake in the forest, proceeded to start dangling his legs over the branch he was sat on, swinging them back and forth.

"Well anyway, before you murder me.." He began, his black pupils noticeably changing into a diamond shape.  
"Lemme check this counterpart out." He said, jumping down from the tree and standing quite a distance away from them.

"Hey little bro, what's your name?" He asked with a grin.  
"His name's Finn.." Cake replied for the human boy.  
"Huh~ I see..." Marshall said, rather amused.  
Finn was rather taken back at both Marshall's pupils changing, and what he just said.

"Hey..what's a counterpart?" Finn asked, unsure. "I have no idea what you're saying!" He called out to Marshall, sounding nervous.

Marshall then proceeded to float over in front of Finn, hands in his pockets. His head was tilted and examining Finn thoroughly with a smirk, which caused Finn to feel uncomfortable. Finn folded his arms, bending slightly back.  
"Y-You going to answer my question or what?" Finn asked, making it clear he was uncomfortable in this situation.  
"..Hah, pretty dumb for a human boy from another dimension, aren't you?" Marshall asked, looking at him sniggering.

"Fionna's more knowledgable than you." Marshall added on. Finn opened his mouth to try and deny it, but Marshall was right. He shut his mouth, biting the inside of his cheek.

Marshall sighed and then tilted his head back and floated not too far in the sky.  
"A counterpart means a person or place with a similar character or form. And that is exactly what you are. The Ooo you know is too." Marshall explained, pointing at Finn.

"Since when has he been so knowledgable?" Fionna spat, her arms folded with a frown.  
"Oh trust me honey, he just wants to show off to the new boy." Cake replied with a smile.

"So...so...this Ooo-"  
"Is the counterpart of your Ooo back home, yes. That's the reason it looks so similar." Marshall interrupted Finn, hands behind his head, closing his eyes peacefully, still floating around.

"It was just a guess of mine that the portal would lead to a different world or dimension or whatever, but proof that my guess was accurate is because you're standing here right now." Marshall opened one of his eyes to see Finn completely lost.

"_**Agh! You still don't get it!?**_" Marshall snapped, floating right in front of Finn's face again.  
"What I'm saying is that I figured out you're from a different dimension and a counterpart of someone in this Ooo!" Marshall concluded. Finn then realised, his eyes widening again.  
"...That's seriously whack..." Finn said quietly, staring blankly into space.  
"Hard to believe, I know." Marshall sighed, deciding to float in the air again. "..Oh and one more thing, Fionna is your counterpart...You're both the same person.."

There was a long pause before the two blonde-haired teens called out in shock.  
"WH-WHAT?!" Fionna and Finn said, not seeing that coming. Cake's jaw dropped after she gasped in shock.  
"Oh please, don't act so surprised. I mean, the same backpack and clothes and character and everything..it's blatantly obvious." Marshall waved his hand offhandedly, letting a yawn interrupt.  
"B-BUT THAT'S WRONG! I CAN'T BE A GIRL! I THOUGHT A COUNTERPART WAS SOMEONE EXACTLY LIKE YOU!"  
"Not exactly, dumbass. I said _si-mi-lar_." Marshall added on.  
"YOU'RE NOT MAKING SENSE MARSHALL!" Fionna snapped. Marshall sighed.

"Well, just try and accept the fact that you're both the same person, then maybe you'll understand something." Marshall replied with another yawn.


	5. Chapter 5

"Uh, honey?...You 'kay?" Cake asked Finn, rather worriedly.

Finn was speechless and sat on the floor. There was now proof this wasn't all a bad dream..he was seriously in the counterpart of Ooo.

But his heart sank. The only human he ever layed eyes on was himself from the moment he had met Fionna...he was all alone. There were no humans left on the earth..the only hope he had left was Fionna...but she wasn't a different person. They were the same.

Cake was worried. She then sighed and looked over at Fionna.  
"He is so not fine..." Cake whispered to Fionna after she had quickly edged away from Finn, frowning, covering her mouth with her paw.

"...Erm...at any rate, Finn...Well...I guess it makes...a bit of sense?" Fionna asked with a nervous giggle, looking over at the boy. She then sat down next to him on the floor, followed by Cake. It was quiet for a few minutes with nothing but the sound of Marshall floating around in the sky.  
"...Oh c'mon! Don't look so down! So what if we're the last on Earth?! We've made lots of friends, right?" She asked, punching him in the arm, urging him to agree.

Finn looked over at Fionna and took a deep breath in, then out. "Yeah. I guess you have a point.." He replied with a smile, rubbing his arm. "It's not that bad..being the last of your kind.."

Marshall Lee couldn't help but snigger.  
"Yeah, well, good luck with sticking to that theory." He called out.. Finn looked up at Marshall with a frown, hugging his own knees.  
"Why are you still here?!" Finn and Fionna growled in unison. They then looked at each other and couldn't help but laugh. Cake's ears then perked up and she grinned, her tail moving side to side.

"You two are so alike, it makes me cringe." Marshall smiled at them both, causing the teens to go crimson.  
"H-Hey, why're you going red?" Finn asked, looking over at Fionna.  
"S-Same to you! Why're you going red?!" Fionna replied with a nervous laugh, both of her hands on her red cheeks.  
"W-What?!" The two of them then proceeded to play fight, wrestling each other on the ground. Cake was watching with a smile.  
"Try not to break both of your bones!" Cake warned.

After a while, Marshall grinned.  
"Well then, now that you dumbasses have realized who is who, I'd best be off." Marshall Lee started, not realizing what they were talking about or wrestling about.

Finn and Fionna were flat on their backs, tired from playing.

"Huh? You're going already?" Fionna asked, rolling over off her back.

"Simonetta wants to make a new song and I promised the old hag I wouldn't let her down." He explained, his body still floating in the air.

"Why the hell do you even hang out with Ice Queen?" Fionna pouted with a frown, looking away.  
"ICE QUEEN!? There's even an Ice Queen!?" Finn asked, shocked.  
"Of course! Defeating her was the reason we became heroes!" Cake explained boldly.

"Well...it's 'cause...she's dear to my heart...and I love her.." Marshall replied hesitantly with a smile.

Finn, Cake and Fionna didn't know what to say.  
When he looked over at Fionna, Finn saw her face going crimson.  
"Hey! Stop going red! It's embarrassing doing that when you're part of me!" He scolded.  
"I-I can't help it! It's that idiot's fault!" Fionna replied, pointing at Marshall, who now had a grin on his face.  
"She has a super massive crush on me." Marshall explained, shrugging, the grin on his face only growing more. He then landed on the floor with his hands in his pockets and turned his back against them, beginning to walk.

"Oh, and I know you'll fall for me too, Finn. Since you and her are so similar after all."  
He added on, his head turned halfway, sticking his tongue out with a sneer.


End file.
